The present invention generally relates to braking systems, and more particularly, to systems and method to determine the presence of a dragging brake.
During takeoff, an aircraft reaches high speeds, and as such, the wheels of the aircraft also rotate at a high rate of speed. Once the aircraft takes off, the wheels begin to “spindown.” Spindown is known in the art as the natural deceleration of wheels after takeoff. Spindown continues until the pilot actuates the landing gear system to retract and store the landing gear in the landing gear bay of the aircraft fuselage.
If a brake on a wheel is dragging (i.e., is at least partially engaged), then the brake may heat itself and/or other landing gear and/or wheel components to a very high temperature. The brake may drag for a number of reasons, including over pressurization of the brake, a parked brake that is too hot because it has not cooled sufficiently after a previous landing and corresponding brake engagement, a broken brake rotor/stator, an improper brake adjustment, ice wedged between the pressure plate of the brake and the actuator, and the like. Brake dragging and the resulting heat are undesirable, because if the wheel and brake are retracted into the bay while hot, there may be an increased risk of failure (for example, the tire may rupture and expel a portion of the tire or wheel through the fuselage, damaging the aircraft).